The invention pertains to a reactor for the gasification of solid, carbonaceous materials in a fluidized bed under elevated pressure and at high temperatures with a feed device for the hot gasification agent, which has at least one bridge-shaped structure attached in the reactor chamber consisting of ceramic refractory material, inside which there is a pipe line for gasification agent running along the bridge essentially in the longitudinal direction, this line being provided with openings pointing downward and/or to the sides, through which the gasification agent can emerge from the bridge into the reactor chamber.
A reactor of this type is known from U.S. patent application Ser. No. 108,194, filed Dec. 28, 1979, now abandoned, which also lists the essential reasons which make it appear advisable that a bridge-shaped structure of this type be used as a feed device for the gasification agent. It has been found, however, that with a view to the functions assigned to such a bridge-shaped structure, special measures must be taken with regard to its design in order to ensure that the desired effect is achieved under all possible operating conditions. This applies primarily with respect to high temperatures, which can be as high as 1,200.degree. C. and more. Metallic materials are not able to withstand such permanent stress over weeks and months, so that the use of refractory ceramic materials is required. However, these do not guarantee gas-tightness, especially since a structure of this type is composed of brick-type ceramic elements. One of the essential preconditions for the achievement of optimum operating conditions is, however, a specific distribution of the hot gasification agents over the cross-section of the reactor chamber, which at the same time also effects the fluidization of the fluidized bed. This results in the requirement that the points at which the gasification agent enters the reactor as well as the amounts of gasification agent per unit of time must be established within certain limits and maintained there.
This would not be possible if the bridge-shaped structure were to consist of ceramic parts exclusively, since, even though the individual bricks of ceramic material were held together by mortar, cracks, gaps, etc. would necessarily occur over the course of time, through which the gasification agent would pass in and out of the reactor chamber in a way which could not be controlled with respect to location or quantity. In addition, within the bridge-shaped feed device, the gasification agent must be under a pressure that is higher than the pressure prevailing in the reactor chamber, so that there is a pressure difference between the line inside the bridge-shaped structure and the reactor chamber. If no special measures are taken, this would result in the creation of forces which would act on the bridge-shaped structure. This would be a definite disadvantage, since the installation would have to be constructed with significantly more strength, e.g. to withstand the pressure forces acting laterally and upwards as well.
One of the purposes of the invention is to design a reactor of the above-described type in such a manner that satisfactory long-term operation can be guaranteed even at very high temperatures and at pressures of up to 120 bar or more, namely with respect to gasification agent distribution that takes into account the technical requirements of both flow and gasification, as well as to design the bridge-shaped installation and the conduit contained therein which would be as simple as possible and require minimum maintenance.